Method of making cardboard articles



METHOD OF MAKING CARDBOARD ARTICLES Filed Jan. 28, 193s Patented Feb. 1,1938 UNITED sTATEs PATENT OFFICE METHOD F MAKING CARD-BOARD ARTICLESApplication January 28, 1936, Serial No. 61,169

6 Claims.

This invention relates to the art of making trays, frames, etc. fromcardboard and similar sheet material, having for its objects tofacilitate the shaping of such die-pressed articles to permit theformation of abrupt bends or folds without cracking or rupturing thematerial, to make the finished articles conform more accurately to thecontour of the shaping dies, to reduce the cost of manufacturing ofjewelry boxes and the like, and generally to improve the art to whichthe invention relates.

In one aspect the present invention comprises a method of making adisplay tray or the like formed of a piece of cardboard having a sectionpermanently depressed below the level of the surrounding portion toprovide a recess for the article to be displayed, the surroundingportion being turned downwardly throughout its outer periphery and beingcontinuous at the corners, in combination with a cardboard bottomcemented to the lower edges of the downturned periphery and preferablyalso cemented to the bottom of the depressed central section. The marginof the cardboard bottom preferably projects outwardly beyond the upperportion of the tray to provide a seat for a cover fitting over the tray.

To facilitate manufacture and to increase the' rigidity of the resultingproduct, the cardboard is preferably formed of a plurality of superposedsheets of flexible material, suchas tough kraft paper, cemented togetherface to face with any suitable cement such as animal glue. In theprocess of manufacture the superposed sheets are preferably die-pressedto shape before the adhesive between the sheets has dried, therebyfacilitating the shaping operation and preventing the cardboard fromcracking or rupturing at sharp corners, folds and bends. After thecardboard has been pressed to shape the cement may be fully dried butthe finished product can be made to conform more accurately to the shapeof the forming dies by again die-pressing the blanks after they havepartially dried but before the cement has completely set.

In another aspect of the invention the articles are made in gang form bysimilarly shaping recurrent sections of a continuous sheet of cardboard,the cardboard preferably being slit throughout the portion to be shapedintermediate the aforesaid sections to facilitate the shaping operation,the slits widening in the shaping operation to permit the material to bepressed into ridges or into irregular formations. After the blanks havethus been made in gang form a continuous piece of cardboard may becemented to the back of the shaped material, after which the individualblanks may be cut apart and trimmed with sections of the backingmaterial adhering thereto and trimmed in the same operation.

For the purpose of illustration typical embodiments of the invention areshown in the accompanying drawing in which Fig. 1 is a plan view withparts broken away showing the preferred cardboard;

Fig. 2 is a similar View showing the'cardboard after it has beendie-pressed to shape;

Fig. 3 is a section on line 3-3 of Fig. 2;

Fig. 4 is a similar section after the backing has been applied;

Fig. 5 is a similar section after the blanks have been cut apart andtrimmed;

Fig. 6 is a plan view of the resulting product, a part being brokenaway;

Fig. 7 is a plan View of another embodimentV of the invention;

Fig. 8 is a section on line 8-8 of Fig. 7

Fig. 9 is a similar section after the blank has been trimmed; and

Fig. 10 is a similar section after the backing has been applied to theblank and a cover has been applied.

The particular embodiment illustrated in Figs. l to 6 inclusivecomprises a backing I of cardboard or the like cemented to the bottom ofa tray comprising a bottom 2, upright inner walls 3, a rim 4 and slopingouter walls 5, the backing l being cemented both to the bottom 2 andalso to the edges of the outer walls 5 as indicated at 6 inv Figs. 4 and5.

As shown in Figs. 1 and 2 the trays are preferably formed from cardboard1 made up of a plurality of layers 8 of paper. As indicated at 9 in Fig.1 the layers 8 are interconnected by coatings of cement 9. After thelayers are cemented together and before they are die-pressed to shapethe cardboard is provided with a plurality of slits lil between theportions which are to be die-pressed. Then the Yportions between theslits I0 are die-pressed to the shape shovm in Figs. 2 and 3 withordinary heated dies having contours corresponding to that of theresulting blank. In this die-pressing operation the slits I0 are widenedas the adjacent material is pressed up to form the ridges constitutingVthe portions 3, 4 and 5 of the resulting tray. After a series of thesetrays are'shaped in gang form as illustrated in Fig. 2 the backingmaterial I is cemented to the back of the die-pressed cardboard.Thereafter the blanks are cut apart and trimmed as shown in Figs. 5 and6.

In the process of making these trays the following procedure isrecommended. While the cement 9 between the sheets is still wet thecardboard is slit and die-pressed. Thereafter it is partially dried,preferably to the extent of approximately 70% of the moisture content,and the cardboard is then again die-pressed, after which the cement iscompletely dried. By first die-pressing the cardboard while the cementis still quite wet, the cardboard may be much more readily shapedwithout danger of cracking or rupturing the paper at the edges andcorners of the ridges; and by again pressing the blanks to shape afterthe cement has largely but not entirely dried the resulting shapecorresponds more accurately with the shape of the dies.

While these articles may be used as picture or mirror frames and forvarious other purposes they are particularly suited for use as jewelrytrays, for which use the interior of the tray, or at least the uppersurface of the bottom 2, is preferably covered with fabric or a padaccording to customary usage in this art. The other exposed portions ofthe articles may be sprayed with lacquer or otherwise suitablydecorated.

The embodiment of the invention illustrated in Figs. 7 to 10 inclusivecomprises a blank having a sloping top I l containing two elongaterecesses I2 and I3 and depending side walls I4. The blanks arepreferably formed from cardboard such as shown in Fig. 1 and after thecardboard has been die-,pressed to shape the flanges I5 are trimmed offas illustrated in Fig. 9. 'Ihe backing I6 is then cemented to the loweredges of the walls I4. The backing I6 projects outwardly beyond thewalls I4 to provide a seat for a cover I1.

It should be understood that the present disclosure is for the purposeof illustration only and that this invention includes all modificationsand equivalents which fall within the scope of the appended claims.

I claim:

1. The method of making articles from sheet material which comprisessuperposing a plurality of sheets with adhesive therebetween to formcomposite sheet material, die-pressing the composite sheet material atrecurrent locations to form a series of blanks each having a downturnedperipheral wall, and then separating the blanks and trimming off thematerial outside said wall.

2. The method of making articles from sheet material which comprisessuperposing a plurality 0f sheets with adhesive therebetween to formcomposite sheet material, die-pressing the composite sheet materialwhile the adhesive is plastic to shape the composite sheet material,causing the adhesive to partially set, again die-pressing the sheet inthe desired shape, and then causing the adhesive to set further.

3. The method of making articles from sheet material which comprisessuperposing a plurality of sheets with adhesive therebetween to formcomposite sheet material, die-pressing the composite sheet material atrecurrent locations to form a series of blanks, joining a continuousbacking to said series, and then simultaneously cutting said materialand backing to form individual blanks with a part of said backingjoinedthereto.

4. The method of making cardboard articles which comprises slitting thecentral zone of a piece of cardboard at recurrent locations-diepressingthe intermediate portions to form blanks including raised portionsproduced by widening said slits, and subsequently trimming ofi thecardboard around each blank. Y

5. The method of making articles from sheet material which comprisessuperposing sheets of iiexible material with adhesive therebetween toform composite sheet material, slitting the central zone of saidcomposite material at recurre-nt locations, die-pressing theintermediate portions to form blanks including raised portions producedby widening said slits, and subsequently trimming 01T the compositematerial around each blank.

6. The method of making cardboard articles which comprises die-pressinga piece of cardboard to form a recess and a surrounding down-turned wallintegrally joined to surrounding cardboard, trimming off saidsurrounding cardboard, and fastening a bottom against the lower edge ofsaid wall.

RUSSELL I. RHODES.

